1. Field
The present invention relates generally to a fastening assembly for securing a heat sink to a printed circuit board, and more particularly to a fastening assembly used for fastening a heat sink to a printed circuit board wherein the fastening can be conveniently released.
2. Prior Art
With advancement of computer technology, electronic devices operate at high speed. It is well known that higher speed the electronic devices operate, more heat they generate. If the heat is not dissipated duly, the stability of the operation of the electronic devices will be impacted severely. Generally, in order to ensure the electronic device to run normally, a heat sink is used to dissipate the heat generated by the electronic device. Moreover, in order to keep the heat sink intimately contacting the electronic device, a fastening assembly is usually desired to secure the heat sink to the electronic device.
Nowadays, numerous fastening assemblies are used to secure heat sinks to electronic devices located on printed circuit board. Typically, a fastening assembly described as follows is used widely. The fastening assembly comprises a lengthwise shaft and a spring member attached to an end of the shaft. A retaining portion is formed at an opposite end of the shaft for engaging with the printed circuit board. The retaining portion comprises a left flexible portion, a right flexible portion and a longitudinal groove defined between the two portions for providing a deforming space to the two portions. In assembly, the retaining portion of the fastening assembly is inserted into a through hole defined in the heat sink and an aperture defined in the printed circuit board. Due to pressure of sidewalls of the hole and the aperture bearing on the retaining portion, the left flexible portion and the right flexible portion are deformed and shrink toward each other, and then pass through the hole and the aperture. Thereafter, the left flexible portion and the right flexible portion come back to their original positions where they are free. Here, the heat sink and the printed circuit board are sandwiched between the retaining portion and the spring member with the retaining portion abutting against the printed circuit board upwardly and the spring member pressing the heat sink toward the printed circuit board. Thus, the heat sink is intimately secured to the electronic device. However, a problem arises out when it comes to the detachment of the heat sink from the electronic device. A tool is desired to get the left flexible portion and the right flexible portion of the retaining portion shrunken toward each other so that the retaining portion can exit out of the aperture of the printed circuit board and the hole of the heat sink. At the present time, what is unfortunate is that space in the computer for the tool to work is more and more limited. Thus, it is inconvenient for the fastening assembly to be detached from the printed circuit board and the heat sink.